• 제목/요약/키워드: direct sampling

검색결과 464건 처리시간 0.031초

The Impact of Organizational Commitment on Employee Motivation: A Study in Vietnamese Enterprises

  • NGUYEN, Hoai Nam;LE, Quoc Hoi;TRAN, Quang Bach;TRAN, Thi Hoang Mai;NGUYEN, Thi Hai Yen;NGUYEN, Thi Thuy Quynh
    • The Journal of Asian Finance, Economics and Business
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    • 제7권6호
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    • pp.439-447
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    • 2020
  • The study examines direct and indirect impacts of organizational commitment on employee motivation through two mediating factors - opportunistic behavior and knowledge sharing - in Vietnamese enterprises. The samples were selected by the non-probability sampling method followed convenient sampling, relatively stratified by localities in Vietnam. The sample size was 636 employees in Vietnamese enterprises. The number of collected online questionnaires was 379, while the number of valid questionnaires was 329. In the direct survey, the number of distributed questionnaires was 750, while the number of collected questionnaires was 421 and the number of valid questionnaires was 307. The total number of valid questionnaires used for analysis was 636. The study used quantitative methods with structural equation modeling analysis. The results indicate that among the components of organizational commitment, normative commitment has both direct and indirect impacts on employee motivation through two mediating factors: opportunistic behavior and knowledge sharing. Meanwhile, affective commitment has only an indirect impact on employee motivation through these mediating factors. Continuance commitment has both direct and indirect impacts; however, it has only an indirect impact on employee motivation through opportunistic behavior. In addition, the results show opportunistic behavior has a negative impact on the knowledge sharing of employees in enterprises.

서울지역 시간별 에어로솔 자료를 이용한 화학성분별 광학특성 및 직접 복사강제력의 시간 변화 분석 (Temporal Variations in Optical Properties and Direct Radiative Forcing of Different Aerosol Chemical Components in Seoul using Hourly Aerosol Sampling)

  • 송상근;손장호
    • 한국대기환경학회지
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    • 제30권1호
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    • pp.1-17
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    • 2014
  • Temporal variations of optical properties of urban aerosol in Seoul were estimated by the Optical Properties of Aerosols and Clouds (OPAC) model, based on hourly aerosol sampling data in Seoul during the year of 2010. These optical properties were then used to calculate direct radiative forcing during the study period. The optical properties and direct radiative forcing of aerosol were calculated separately for four chemical components such as water-soluble, insoluble, black carbon (BC), and sea-salt aerosols. Overall, the coefficients of absorption, scattering, and extinction, as well as aerosol optical depth (AOD) for water-soluble component predominated over three other aerosol components, except for the absorption coefficient of BC. In the urban environment (Seoul), the contribution of AOD (0.10~0.12) for the sum of OC and BC to total AODs ranged from 23% (spring) to 31% (winter). The diurnal variation of AOD for each component was high in the morning and low in the late afternoon during the most of seasons, but the high AODs at 14:00 and 15:00 LST in summer and fall, respectively. The direct negative radiative forcing of most chemical components (especially, $NO_3{^-}$ of water-soluble) was highest in January and lowest in September. Conversely, the positive radiative forcing of BC was highest in November and lowest in August due to the distribution pattern of BC concentration.

Measurement of Imaging Property of Flat-Panel Detector

  • Matsumoto, Masao;Suekane, Kouji;Maeda, Kouji;Ogata, Yuji;Inamura, Kiyonari;Kanai, Kouzo;Kanamori, Hitoshi
    • 한국의학물리학회:학술대회논문집
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    • 한국의학물리학회 2002년도 Proceedings
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    • pp.385-388
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    • 2002
  • We measured and evaluated digital, pre-sampling and overall imaging properties (characteristic curves, Modulation Transfer Function (MTF), Wiener spectra (WS), Noise Equivalent Quanta (NEQ) and Detective Quantum Efficiency (DQE)) for the direct type and indirect type of Flat-Panel Detector (FPD). First, the digital and overall characteristic curves of the both types of FPD had more wide dynamic range than that of the S/F system. Second, the pre-sampling and overall MTF of the direct-type FPD were superior to those of the indirect-type FPD. Third, for identical exposures, the digital and overall WS of the direct-type FPD were similar or worse than those of the indirect-type FPD, and for larger exposure, the digital WS of the both types of FPD were smaller, but overall WS of the both types of FPD were larger. Fourth, the digital and overall NEQ and DQE of the direct-type FPD were worse than both NEQ and DQE of the indirect-type FPD at lower spatial frequencies, but were better at higher spatial frequencies.

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Fluorescence Characteristic Spectra of Domestic Fuel Products through Laser Induced Fluorescence Detection

  • Wu, Ting-Nien;Chang, Shui-Ping;Tsai, Wen-Hsien;Lin, Cian-Yi
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제19권5호
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    • pp.18-25
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    • 2014
  • Traditional investigation procedures of soil and groundwater contamination are followed by soil gas sampling, soil sampling, groundwater sampling, establishment of monitoring wells, and groundwater monitoring. It often takes several weeks to obtain the analysis reports, and sometimes, it needs supplemental sampling and analysis to delineate the polluted area. Laser induced fluorescence (LIF) system is designed for the detection of free-phase petroleum pollutants, and it is suitable for on-site real-time site investigation when coupling with a direct push testing tool. Petroleum products always contain polycyclic aromatic hydrocarbon (PAH) compounds possessing fluorescence characteristics that make them detectable through LIF detection. In this study, LIF spectroscopy of 5 major fuel products was conducted to establish the databank of LIF fluorescence characteristic spectra, including gasoline, diesel, jet fuel, marine fuel and low-sulfur fuel. Multivariate statistical tools were also applied to distinguish LIF fluorescence characteristic spectra among the mixtures of selected fuel products. This study successfully demonstrated the feasibility of identifying fuel species based on LIF characteristic fluorescence spectra, also LIF seemed to be uncovered its powerful ability of tracing underground petroleum leakages.

Comparison of Two Methods for Measuring Daily Path Lengths in Arboreal Primates

  • Lappan, Susan
    • Journal of Ecology and Environment
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    • 제30권2호
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    • pp.201-207
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    • 2007
  • Researchers have used a variety of methods to measure patterns of animal movement, including the use of spatial data (mapping the position of a moving animal at specified intervals) and direct estimation of travel path length by pacing under a moving animal or group. I collected movement data from five groups of siamangs (Symphalangus syndactylus) using two different methods concurrently to estimate the effects of the method of data collection on estimates of daily path length (DPL). Estimates of DPL produced from spatial data collected at 15-minute intervals were 12% lower than estimates of DPL produced by pacing under the traveling animal. The actual magnitude of the difference was correlated with the travel distance, but there was no correlation between the proportional difference and the travel distance. While the collection of spatial data is generally preferable, as spatial data permit additional analyses of patterns of movements in two or three dimensions, the relatively small difference between the DPL's produced using different methods suggests that pacing is an acceptable substitute where the collection of spatial data is impractical. I also subsampled the spatial data at increasing time intervals to assess the effect of sampling interval on the calculation of daily path lengths. Longer sampling intervals produced significantly shorter estimates of travel paths than shorter sampling intervals. These results suggest that spatial data should be collected at short time intervals wherever possible, and that sampling intervals should not exceed 30 minutes. Researchers should be cautious when comparing data generated using different methods.

Stochastic cost optimization of ground improvement with prefabricated vertical drains and surcharge preloading

  • Kim, Hyeong-Joo;Lee, Kwang-Hyung;Jamin, Jay C.;Mission, Jose Leo C.
    • Geomechanics and Engineering
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    • 제7권5호
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    • pp.525-537
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    • 2014
  • The typical design of ground improvement with prefabricated vertical drains (PVD) and surcharge preloading involves a series of deterministic analyses using averaged or mean soil properties for the various combination of the PVD spacing and surcharge preloading height that would meet the criteria for minimum consolidation time and required degree of consolidation. The optimum design combination is then selected in which the total cost of ground improvement is a minimum. Considering the variability and uncertainties of the soil consolidation parameters, as well as considering the effects of soil disturbance (smear zone) and drain resistance in the analysis, this study presents a stochastic cost optimization of ground improvement with PVD and surcharge preloading. Direct Monte Carlo (MC) simulation and importance sampling (IS) technique is used in the stochastic analysis by limiting the sampled random soil parameters within the range from a minimum to maximum value while considering their statistical distribution. The method has been verified in a case study of PVD improved ground with preloading, in which average results of the stochastic analysis showed a good agreement with field monitoring data.

Does Audit Committee Quality Mediate Determinants of Intellectual Capital Disclosure?

  • ASTUTI, Resa Nur;FACHRURROZIE, Fachrurrozie;AMAL, Muhammad Ihlashul;ZAHRA, Siti Fatimah
    • The Journal of Asian Finance, Economics and Business
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    • 제7권7호
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    • pp.199-208
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    • 2020
  • This study investigates the direct and indirect effects, mediated by audit committee quality, of managerial ownership, institutional ownership, and profitability on intellectual capital (IC) disclosure. The object observed of this study is companies listed on the Indonesia Stock Exchange (IDX) in the 2014-2018 period that are classified as high intellectual capital-intensive industries. Based on the sampling method, purposive sampling, 51 companies were selected as samples. This study used path analysis techniques with IBM SPSS version 25 to study the direct and indirect influences of managerial ownership, institutional ownership, and profitability toward IC disclosure. The results of this study show that managerial ownership, profitability and audit committee quality have a significant positive effect on IC disclosure whereas institutional ownership has significant negative effect on IC disclosure. This study also provides empirical evidence, supported by the sobel test, that the audit committee quality is able to mediate the effect of institutional ownership and profitability on IC disclosure. However, the audit committee quality is not able to mediate the effect of managerial ownership on IC disclosure. These findings develop and strengthen the results of prior studies related to the implementation of signaling theory and agency theory in devoting more understanding about IC disclosure.

주조 포오스트의 적합도에 관한 연구 (A STUDY ON THE ADAPTATION OF THE CAST POST)

  • 박동관;장익태
    • 대한치과보철학회지
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    • 제24권1호
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    • pp.55-65
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    • 1986
  • An in vitro study was performed to evaluate adaptation of custom direct, custom indirect, and prefabricated post system on 15 extracted upper central incisors. 15 specimens were prepared and equally devided into 3 groups under random sampling. Each group of 5 cast posts was made with custom direct, custom indirect, and prefabricated post core method. Gap between inner wall of the dentin and outer wall of the cast post was measured on electron microphotographic prints at x500 magnification. The result were as follows ; 1. No significant difference of adaptation at cervical portion was found between each method. 2. Prefabricated post core method had poor adaptation compared with other methods. 3. Even distribution of adaptation was found in custom direct method between each portion. 4. Prefabricated post core method showed remarkable difference in adaptation between each portion.

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Shape Optimization to Minimize The Response Time of Direct-acting Solenoid Valve

  • Shin, Yujeong;Lee, Seunghwan;Choi, Changhwan;Kim, Jinho
    • Journal of Magnetics
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    • 제20권2호
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    • pp.193-200
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    • 2015
  • Direct-acting solenoid valves are used in the automotive industry due to their simple structure and quick response in controlling the flow of fluid. We performed an optimization study of response time in order to improve the dynamic performance of a direct-acting solenoid valve. For the optimal design process, we used the commercial optimization software PIAnO, which provides various tools for efficient optimization including design of experiments (DOE), approximation techniques, and a design optimization algorithm. 35 sampling points of computational experiments are performed to find the optimum values of the design variables. In all cases, ANSYS Maxwell electromagnetic analysis software was used to model the electromagnetic dynamics. An approximate model generated from the electromagnetic analysis was estimated and used for the optimization. The best optimization model was selected using the verified approximation model called the Kriging model, and an optimization algorithm called the progressive quadratic response surface method (PQRSM).